Instantaneously variable electromechanical time fuze



April 26, 1960 ER 2,934,015

INSTANTANEOUSLY VARIABLE ELECTRO-MECHANICAL TIME FUZE Filed Aug. 31, 1956 VOLTAGE SOURCE GAS DIODE |2 /TRIGGER TUBE II \VARIABLE I CLOCK CONDENSER t MECHANISM v PRIMER INVENTOR. DONALD F. HERDMAN ATTORNEYS.

United States Patent ""ce INSTANTANEOUSLY VARIABLE ELECTRO- MECHANICAL TIME FUZE Donald F. Herdman, China Lake, Calif., assignor to the United States of America as represented by the Secretary of the Navy The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalty thereon or therefor.

The present invention relates to an instantaneously variable electro-mechanical time fuze in which a variable condenser is varied by means of a time clock. A voltage is originally supplied to the condenser, and when a missile which houses the fuze is fired, the voltage is removed and a time clock is set in motion which decreases the capacitance linearly with time. As the capacitance is decreased the voltage is increased until the striking voltage of a gas diode, which is connected in series with the condenser, is reached. At that time the condenser energy will be discharged into the primer and the missile exploded.

Previous mechanical clocks have time settings manually set. Other mechanisms utilize condenser discharge circuits involving voltage sensitive tubes. Manually set mechanical clocks have the disadvantage of slow adjustment, and time setting cannot be conveniently and immediately set by gun control systems. The present invention overcomes the disadvantages of the prior systems by providing a system of instantaneously setting a mechanical clock by means of a variable condenser charged with an electrical voltage corresponding to the time delay desired, and by firing a gas tube by means of a variable condenser which is varied by the clock.

The principal object of the invention, therefore, is to provide an improved system of instantaneously setting a mechanical clock with a desired time delay.

Another object of the invention is to provide a system of firing a gas tube by means of a variable condenser which is varied by means of a mechanical clock.

A further object of the invention is to provide an electro-mechanical time fuze which can be easily and instantaneously set, and does not require manual time setting.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same become better understood by reference to thefollowing detailed description when considered in connection with the accompanying drawing wherein:

The figure is a diagrammatic showing of the present invention.

The present invention can beconstructed using a conventional type of time clock as used in prior systems. As is illustrated in the figure, the time clock mechanism is connected to the turning shaft 11 of a variable condenser 12. The variable condenser 12 is charged from a source of variable voltage applied across terminals 14 and 15; this voltage charging replaces the manual time setting required in prior systems. The voltage source is disconnected by an acceleration actuated switch 16.

At zero time the mechanical clock 10 is ready for timing and the variable condenser 12 is fully meshed at maximum capacitance. Condenser 12 is charged with 2. voltage directly related to the time delay desired. When the clock mechanism 10 is started, at the time the voltage source is disconnected by the opening of switch 16, the

2,934,015 pres A capacitanceof variable condenser 12 will decrease linearly with time and the original voltage of the condenser will increase continuously with the reduction of capacitance. A voltage sensitive gas diode 18 in series with an electrical primer 20 is connected in parallel with the variable condenser 12. When the voltage of condenser 12 reaches the striking voltage of the diode 18, the condenser energy will be discharged into the primer 20. This arrangement allows the time fuze to be instantaneously set for a chosen time delay, thus avoiding complex quick setting mechanical setting apparatus. Safety devices and additional electrical circuitry to supply more energy to the primer may be added to the system if desired.

Obviously, many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. An instantaneously variable electro-mechanical time fuze comprising a mechanical clockwork, a variable condenser, one set of plates of said condenser being attached to said clockwork in such a manner that operation of the clockwork progressively decreases the capacitance of said condenser, a source of variable voltage, means to charge said condenser with a given selected voltage from said source and means for cutting ofi said voltage source, an electrically operable primer, and a voltage sensitive gas diode in series with said electrically operable primer, said series connected diode and primer being in parallel with said variable condenser, whereby as the capacitance of said condenser decreases the original voltage increases until, at the desired predetermined time, the striking energy of the diode is reached and the condenser energy is discharged into the primer.

2. An instantaneoulsy variable time fuze comprising a variable condenser, means connected to one set of plates of said condenser for varying the plates to progressively decrease the capacitance of said condenser, a source of variable voltage, means to charge said condenser with a given selected voltage from said source and means for cutting ofi said voltage source, an electrically operable primer, and a voltage sensitive gas diode in series with said electrically operable primer, said series connected diode and primer being connected in parallel with said variable condenser, whereby as the capacitance of said condenser decreases the original voltage increases until, at the desired predetermined time, the striking energy of the diode is reached and the condenser energy is discharged into the primer.

3. An instantaneously variable time fuze comprising a variable condenser, means connected to said condenser for varying it to progressively decrease its capacitance, a variable voltage source, means to charge said condenser with a given selected voltage from said source and means for removing said voltage source, an electrically operable primer, a voltage sensitive gas diode being connected in parallel with said variable condenser, the voltage of said condenser increasing as the capacitance of said condenser is decreased, said diode triggering when the voltage of the condenser reaches the striking voltage of the diode and allowing the condenser energy to be discharged into the primer.

4. An instantaneously variable electro-mechanical time fuze comprising a mechanical clockwork, a variable condenser, a shaft connecting said condenser to said clockwork for varying the same and in such a manner that operation of the clockwork progressively decreases the capacitance of the condenser, a source of variable voltage, means to charge said condenser with a given selected voltage from said source and means for disconnecting said voltage source, an electrically operable primer, and a voltage sensitive 'gas diode in series with said electrically operable primer, said series connected diode and primer being connected in parallel with said variable condenser, the voltage of said condenser increasing as the capacitance of said condenser is decreased, said diode triggering when the voltage of the condenser reaches the striking voltage 4 of the diode and allowing the condenser energy to be discharged into the primer.

5. A device as in claim 4 wherein the capacitance decreases linearly with time.

No references cited. 

